Resveratrol affects CYP1A expression in rainbow trout hepatocytes

Area of Science:

• Environmental Toxicology
• Biochemistry
• Aquatic Toxicology

Background:

• Resveratrol (RVT) is a known aryl hydrocarbon receptor (AhR) antagonist in mammals.
• A reliable AhR antagonist is needed for research in rainbow trout (Oncorhynchus mykiss).

Purpose of the Study:

• To evaluate Resveratrol (RVT) as an AhR antagonist in rainbow trout hepatocytes.
• To investigate the dose-dependent effects of RVT on AhR signaling and CYP1A expression.

Main Methods:

• Primary trout hepatocytes were cultured and exposed to varying doses of RVT and beta-naphthoflavone (BNF).
• CYP1A and AhR protein expression were measured.
• Transcriptional and translational inhibitors (actinomycin D, cycloheximide) were used to elucidate mechanisms.
• CYP1A1 mRNA levels were quantified.

Main Results:

• BNF increased CYP1A and AhR protein, an effect inhibited by high doses of RVT (10(-5)-10(-7) M).
• Low doses of RVT (10(-8)-10(-10) M) alone significantly increased CYP1A protein expression.
• RVT's induction of CYP1A was regulated transcriptionally and translationally.
• Low-dose RVT (10(-9) M) increased CYP1A1 mRNA in BNF-primed hepatocytes.

Conclusions:

• Resveratrol functions as an AhR antagonist in trout hepatocytes.
• RVT exhibits a dual role, antagonizing AhR at high concentrations and inducing CYP1A expression at lower concentrations (<10(-8) M).
• These findings highlight the complex effects of RVT in piscine systems and its potential as a research tool.